In certain fields of industry, workers can be exposed to heat and to flame. They therefore need to wear protective clothing made from specially adapted textile yarn. Protective clothing is the subject of standards designed to guarantee a protection threshold. Particular mention can be made of the standard EN 531.
On another topic, it is sometimes required that clothes be bright in color in order to present great visibility, so as to give warning that workers are present. Thus, yarn is available in the following colors: royal blue, fluorescent yellow, fluorescent orange, fluorescent red. Using clothes of different colors can serve as a distinctive sign, making it possible, for example, to distinguish between a plurality of teams on a worksite or a zone where action is being taken. Bright colors for workers' clothing vary over a wide range of shades.
Thus, for example, yarn of royal blue color is known which enables a good level of visibility to be obtained. Yarn is also known of yellow color, of orange color, and of red color that enable a level of visibility to be obtained that satisfies visibility criteria such as those defined in standard EN 471, for example.
In several sectors of activity, it is necessary for workers to wear clothing that simultaneously provides protection against the risks associated with fire and that is also bright in color, and in particular highly visible. For this purpose, brightly colored yarn, in particular yellow yarn, is known that satisfies the criteria of high visibility and protection against fire. The yarn is intrinsically resistant to heat and it contains yellow pigments.
That solution is not suitable, for example, for obtaining yarn of high visibility orange color satisfying the criteria of standard EN 471 and also providing protection against heat. No yarn of fluorescence orange color is known that confers satisfactory fire protection.